It is recognized in the fishing alarm prior art that there are numerous means to alert sportsmen to the presence of strikes on unwatched fishing lines, including expensive radio transmitters as specified in U.S. Pat. Nos. 4,928,419 and 4,996,788. However, one of the more cost-effective alarm mechanisms used in ice fishing is the tip-up device, which commonly includes a brightly-colored flag as a primary means to effect such notice. This visual method of notice has been augmented with other electronic signaling devices, such as buzzers and/or lights that are attached to the tip-up arm at various points and utilize switches to complete a circuit between a power source, such as a battery, and the alarm mechanism when the arm swings from a generally horizontal to a generally vertical position. Examples of various embodiments of such devices may be found in U.S. Pat. Nos. 3,359,673, 5,067,269, 5,488,796, and 5,979,101. The switches used in these devices however are not optimal and present difficulties that include environmental hazards, fouling, and poor overall utility.
Those that employ a removable strip or plate as a circuit-interrupter, wherein the upward motion of the flag arm attached to the circuit-interrupter via a wire or string removes the circuit-interrupter and closes the circuit, such as described in U.S. Pat. Nos. 4,727,673 and 5,097,618, are prone to fouling in icy conditions.
Those utilizing mercury switches, such as defined in U.S. Pat. Nos. 4,928,419 and 5,488,796 for example, present an environmental hazard and may lose effectiveness over a period of time as the mercury evolves from its housing.
And those utilizing gravity-actuated ball-type switches, such as that presented in U.S. Pat. No. 5,979,101, are unreliable in that they sometimes fail to make the proper connection necessary to complete the circuit because the ball does not align in its correct position. Such switches can also be difficult to re-set for their next use and difficult to store in a non-triggered position.
There is therefore a need for a tip-up alarm system utilizing an improved switch design that is environmentally-friendly, reliable, and easy to re-use.